Though everyone recognizes the image of Vitruvian Man, few have any idea what prompted Leonardo da Vinci to create a drawing of a four-armed, four-legged human inscribed by a circle and a square. It was, in fact, the embodiment of the idea of man as microcosm of all creation, as the author of The Fourth Part of the World tells us in this fascinating cultural history. Toby Lester gives us the architect Vitruvius, emperor Caesar Augustus and his "body of empire," visionary mystic Hildegard of Bingen, book-hunter Poggio Bracciolini, dome-builder Filippo Brunelleschi, and, of course, Leonardo himself, whose ghost Lester resurrects in the surprisingly unfamiliar context of his own times.

"One of the great contributions of books like this is to keep the reader from taking for granted a familiar object. Lester's detective story has a satisfying number of insights ... covers a broad swath of history ... [and] braids intellectual threads—philosophy, anatomy, architecture, and art—together in a way that reaffirms not only Leonardo's genius but also re-establishes the significance of historical context in understanding great works of art."—Publishers Weekly (starred review)